QUERY PLAN
GroupAggregate (cost=54.23..54.42 rows=10 width=12)
Group Key: parent_id
-> Sort (cost=54.23..54.26 rows=12 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..54.02 rows=12 width=4)
Filter: (parent_id = ANY ('{1356,1358,1596,1734,1823,1830}'::integer[]))